A Study To Determine: Should Conventional Amounts Of Eye Muscle Surgery For Horizontal Binocular Deviations Be Changed When Oblique Muscle Weakening Procedures Are Simultaneously Performed?

Purpose: To investigate the final surgical outcome in horizontal strabismus correction, measured in primary position of gaze, in two situations: 1. When surgery was performed only on the horizontal rectus muscles; and 2. When inferior or superior oblique muscle weakening procedures were simultaneously performed. Methods: Two hundred thirty cases were analyzed retrospectively: 172 esotropias (110 without oblique overaction; 23 with inferior oblique overaction; and 39 with superior oblique overaction), and 58 exotropias (25 without oblique overaction; 19 with inferior oblique overaction; and 14 with superior oblique overaction). Initial and final deviations, as well as the amount of correction achieved, was compared in six groups. Results: No differences in outcomes and final results were found between any of the major or minor groups of patients. Conclusions: Oblique muscle weakening, in combination with horizontal muscle strabismus surgery did not affect the final results of the horizonal surgery in primary position. This study did suggest that there might not be a need for increasing or decreasing amounts of surgery on the horizonal rectus muscles to correct eso- or exotropia when oblique weakening procedures are included.2012125Stager, D.R., Parks, M.M., Inferior oblique weakening procedures. Effect on primary postiion horizontal alignment (1973) Arch Ophthalmol, 90, pp. 15-16Shuey, T.F., Parks, M.M., Friendly, D.S., Results of combined surgery on the superior obqliue and horizontal rectus muscles for A-pattern horizontal strabismus (1992) J Pediatr Ophthalmol, 29, pp. 199-201Curi, R.L.N., Hipertropias - Disfuncoes de retos e obliquos (1993) Estrabismo, pp. 154-162. , Souza-Dias CR, Almeida HC eds. Roca, Sao PauloPrieto-Diaz, J., Souza-Dias, C.R., Las anisotropias en a y V com disfunctiones de los musculos obliquos. Consideraciones clinico-quirurgicas (1996) Estrabismo, p. 355. , Prieto-Diaz J, Souza-Dias CR eds. La Plata, Jorge de PochBerke, R.N., Tenotomy of the superior oblqiue for hypertropia (1946) Trans Am Ophthalmol Soc, 44, p. 304Jin, Y.H., Sung, K.R., Kook, M.S., The immediate effet of bilateral superior oblique tenotomy on primary position horizontal binocular alignment (1999) Binocul Vis Strabismus Q, 41, pp. 33-38Prieto-Diaz, J., Tenectomia parcial posterior del obliquo superior (1976) Arch Oftalmol B Aires, 51, p. 267Prieto-Diaz, J., Disinsertion of the superior oblique for A pattern anisotropia (1987) Binocul Vis, 2, pp. 7-14Apt, L., Call, B., Inferior oblique muscle recession (1978) Am J Ophthalmol, 85, pp. 95-100Monteiro De Carvalho, K.M., Simoes, A.M., Moreira Filho, D.C., Kara-Jose, N., Efficacy of posterior tenectomy of the superior oblique for a pattern anisotropia (1995) Update on Stabismus and Pediatric Ophthalmology, pp. 322-325. , CRC Press, Boca RatonMinguini, N., Carvalho, K.M.M., Surgical treatment of "A" anisotroipa by superior oblqiue weakening: Posterior tenectomy in comparison with disinsertion (1997) Arq Bras Oftal, 60, pp. 502-50